1. Field of the Invention
This invention relates to apparatus and methods for forming curved articles from elongated workpieces and more particularly, this invention relates to apparatus and methods for forming curved surgical needles from elongated needle blanks.
2. Discussion of the Related Art
Surgical needles are readily available in many different configurations; for example, straight, bowed and highly curved. Curved needles are advantageous over other needle configurations in many surgical procedures for a variety of reasons, among which are uniformity of entry depth for multiple sutures and proper "bite" of the tissue surrounding the incision or wound. It is extremely important, therefore, that each needle be manufactured to meet stringent performance specifications. Inconsistency of curvature of the finished needles could mean the difference between a successful, unremarkable surgical procedure or further injury to a patient resulting from improperly formed needles.
It is known in the prior art to form curved surgical needles by bending wire about a mandrel whose surface contains the desired curves. It is further known that because needles are made of steel or similar springy materials, the mandrel used should have tighter curves than those desired in the final needle to allow for some springback after the bending operation. A disclosure of such features may be found in, for example, U.S. Pat. No. 4,524,771 to McGregor et al. The demand for such precision made needles is great enough to make the costs of producing them manually or by other conventionally slower methods much higher than if they could be produced more rapidly. A continuing need still exists, therefore, for an apparatus which can consistently and rapidly form curved needles from flat needle blanks of differing materials, in order to assure that each curved needle is formed having virtually the same curvature.